Internal combustion engine



Oct. 11, 1932- J. J. M ELHINNEY 1,832,513

INTERNAL COMBUSTION ENGINE Filed June 9. 1930 IA/ l/ENTOR g wag M44ATTORNEYS i atented Oct 11, 1932 JAMES JOHNSTONE MCELHINNEY, OF

PATENT oFFicr.

sUn-REY'H-ILLS, VICTORIA, AUSTRALIA INTERNAL COMBUSTION ENGINEApplication filed J une 9, 1930, Serial No My invention relates toimprovements in internal combustion engines in which a heavy oil mixtureis used in the cylinder and an auxiliary ignition charge of petrol orlike volatile spirit- (referred to hereinafter as petrol mixture) isprovided in the vicinity of thespark plug; and the objects 01": myinvention are, first, to use the petrol mixture more efliciently and tomaintain it in the neighbourhood of the spark plug so asto pre ventwaste; second, to provide meansior scavenging out the burnt petrol gasesinto the cylinder; and, third, to provide means to allow a petrolmixture only to be fed to the cylinder for starting up and idling, I

attain these objects by the mechanism illustrated in the accompanyingdrawing in which V Figure 1 is a vertical section through the head of acylinder showing in position an attachment constructed according to thisinvention.

Figure 2 is a similar view showing the position of the valve of theattachment during starting-up and idling, and

Figure 3 is a plan view of the top or" the attachment showing the meansfor holding the valve of the attachment open during starting-up andidling.

Similar numerals refer to similar parts throughout the several views.

The cylinder 1 is supplied with a crude oil mixture from a vapourizerand carburettor (not shown), as is well known especially in relation totractors, but instead of inserting the spark plug into the threadedsocket 2 in the cylinder the attachment forming the subj ect of thepresent invention is secured therein. The attachment is securedrinposition by a threaded pipe 3 which is adapted to be screwed into thethreaded socket 2 and is provided with an integral flange 4 to which aflange 5 of an upper member is secured by bolts 6. This upper member isprovided with an inlet pipe 7 connected to a petrol carburettor andhaving an ignition chamber 8 for the petrol mixture. The chamber 8 hasan offset threaded socket arm 9 adapted to receive the spark plug. Thepipe 3 has a passageway 13 and is extended upwardly into .4so,oso, andin Australia ru e 11, 1929. p

the petrol chamber to torma valve seat 11 upon which a valve 12 isadapted to rest during the suction stroke of the engine so as to. closethe passageway in thepipe 3. This passageway connects the ignitionchamber 8 to the cylinder except during the induction stroke of theengine. A relatively small bypass passage from the ignition chamber tothe passageway 13 is provided at all times by small ports 15 of anydesired number so that during the induction stroke burnt gases are drawnfrom the ignition chamber through the by-pass and then downwardly intothe cylinder and at the same time are replaced by fresh petrol mixture.The valve is provided with a stem 16 extending upwardly through achamber 17 which forms a reservoir for petrol mixture between the petrolcarburettor and the ignition chamber and th-rougha top chamber 18 whichhouses a spring 19 bearing at one end upon the base 20 of the upperchamber and at thev other end against a cross pin 21 on the valve stem.

A core 22 holds the spring in position. A second valve seat 23 isprovided and when the induction ceases the spring raises the valveagainst this upper valve seat and thus cutsoll the ignition chamber fromthe carburettor and connects it to the cylinder. The spark ignites thepetrol mixture and the flame penetrates into the crude oil mixture andignites it. On the exhaust stroke of the engine the burnt' gases are notscavenged from the ignition chamber and passageway 18 but on theinduction stroke the valve is drawn down against its lower seat and theburnt gases in the ignition chamber are drawn out through the bypass andfrom the main passageway into the cylinder and their place is taken'by afresh charge of petrol mixture. The capacity of the ignition chamber andpassageway 13 is so small in relation to that of the cylinder that thepresence of this small'quantity of burnt petrol gases in the crude oilmixture in the cylinder does not substanti'allyafiect the efiicientcombustion of the latter. The size of the by-pass is so designed that onthe completion of the induction stroke the petrol charge will be drawndown to the base of the passageway .Figure 2 so that the petrol mixture13 but will not be drawn into the cylinder to any substantial extent, ifat all, and the passageway 13 and the ignition chamber 8 are soproportional that on the compression stroke the petrol charge iscompressed in the ignition chamber but the crude oil mixture does notpass beyond the top of the passageway to any substantial extent, if atall. Consequentl a rich petrol charge is ignited in the i nition chamberwhile it is in close con- 6 1 b J L tact with the crude oil mixture, andat the same time, waste of petrol by drawing an unnecessary amount intothe cylinder is avo1ded.

To prevent overheating of the spring,

cylinder through the top of the passageway 13 with the result that amuch greater quantity is drawn in than when the suction is through thebypass ports 15 alone.

This means comprises a half collar 2% carried by an arm 25 pivoted to abracket 26 on the top of the attachment. A spring 27 tends to hold thehalf collar away from the stem 16 of the valve but the half collar canbe drawn in by means of a Bowden wire 29 so as to engage the valve stem.The valve stem is provided with a collar 30 at the top which preventsthe valve falling when the valve stem is engaged by the half collar.

The valve is then held in the position shown in i may be drawn in forstarting-up and idling. When starting-up the engine, as soon as warmedup sufliciently the Bowden wire is released allowing the half collar tofly out away from the valve stem under the action of its spring 27 andthe valve 12 is then free to close vupon the lower seat 11 on theinduction stroke of the engine. As soon as the valve is thus tree tooperate, the crude oil mixture is supplied to the engine cylinder.

Then it is desired to allow the engine to idle as, for example, whena-block occurs in the trafiic, the foot is removed from the acceleratorso as to cut oii the-supply of crude oil mixture and the Bowden wire isoperated to force the half collar inwards. It the valve stem is not inits raised position when the half collar is forced inwards it will ofcourse almost instantly rise owing to the rapidity of the engine cycleandthe half collar will then slip into place to hold the valve open 'asshown in Figure 2. The arms 25 of the various cylinders of the engineare linked together by adjustable rods 28.

it has I claim: 1 A g 1. In a four-stroke cycle internal combustionengine the combination of an engine cylinder for the combustion of heavyoil mixture, a petrol mixture ignition chamber con nected to saidcylinder, a pipe forming a passageway between said ignition chamber andsaid cylinder, a valve adapted to close the main opening of saidpassageway into said ignition chamber, a by-pass between said ig- 7nition chamber and saidpassageway and of smaller cross section than saidpassageway, a socket in the wall of said ignition chamber to accommodatea spark plug, and means adapted to cut off the supply of petrol mixturefrom said ignition chamber except during the induction stroke of theengine.

2. An internal combustion engine as claimed in claim 1 in which the saidvalve and the said means adapted to cut off the supply of petrol mixturefrom the ignition chamher are constructed integrally with each other asa double valve member of unitary structure adapted to close alternatelyon a -iirst valve seat andja second valve seat. 1 {as 3. in afour-stroke cycle internal combustion engine, the combination or" anengine cylnder for blli'} combustion of heavy oil mixture, an ignitionchambenlmeans connecting said ignition chamber to said cylinder forytfispark plug ignition, a first valve seat on said connecting means, adouble valve member adapted to engage said first valve seat on theinduction stroke of the engine, a second valve seat normally engaged bysaid valve memberlee and cutting oh the supply of petrol mixture exceptduring the induction stroke of theengine, a valve stem connected to saidvalve member, a spring associated with said valve stem and adapted tohold said valve memberajlo5 against said second valve seat, by-passmeans connecting said ignition chamber to said cyl-' inder even whensaid valve member is'closed against said first valve seat ontheinduction stroke of the engine, and means adapted tog lio engage saidvalve stem and prevent said valve member from closing on said firstvalve seat during starting-up and idling. V

In testimony whereof I aflix my signature.

JAMES JOI-TNSTONE MGELHINNEY. 2-1

